Basic azo-dyestuffs and their production



Patented Jan. 18, 1938 UNITED A1 r ses BASIC AZO-DYESTUFFS AND THEIR PRO- DUCTION No Drawing. Application February 6, 1934, Se-

rial No. 709,949. In Germany February '7,

4 Claims.

Method of producing basic azo-dyestufis It has been found that it is possible to obtain most valuable basic azo-dyestuffs of quite new dyeing effects in coupling arylides of hydroxyor ketocarboxylic acids serving as coupling components with diazonium compounds containing a quaternary ammonium residue, or in using as coupling components hydroxyor keto-carboxylic acid arylides containing a quaternary ammonium residue in the molecule. In the latter case the presence of a quaternary ammonium residue in the molecule of the diazo-component is not absolutely necessary. The special constitution of the quaternary ammonium residue is not material for the present procedure. One of the hydrocarbon residues fixed at the nitrogen, atom must be of an aromatic or fatty-aromatic character while the others may belong to the aliphatic, alicyclic, aromatic and fatty-aromatic series. The nitrogen atom may, however, also belong to a heterocyclic ring-system such as the pyridine-, quinoline-, piperidineand phenazine ring-systems. Among the hydroxyor ketocarboxylic acids to be considered for the present method there may be mentioned: aceto-acetic acid, benzoyl acetic acid, oxal-acetic acid, acetone dicarboxylic acid, salicylic acid, p-cresotinic acid, p-hydroxybenzoic acid, 2,3 -hydroxynaphthoic acid, 2-hydroxyanthracene3-carboxylic acid, 2- hydroxyphenanthrene-3-carboxylic acid, 3-hydroxyphenanthrene-2-carboxylic acid, Z-hydroxycarbazol-S-carboxylic acid, 8-hydroxyquinoline- 5-carboxylic acid. For the condensation with these as Well as with analogously constituted ketoand hydroxy-carboxylic acids it is permissible to use any aromatic monoor diamines such as aniline and its homologues and nuclear substitution products, 21- and e-naphthylamine, and furthermore diamines such as mor pphenylenediamine, benzidine and its nuclear substitution products, tolidine, dianisidine, p, pdia-minodiphenylamine and similar diamino compounds which are capable of condensing with two molecules of the hydroxycarboxylic acid.

There is also a great choice among diazo components applicable according to the present invention, e. g. the salts of the trimethyl-(mor p-azninophenyl-mmmonium and of the mor p-aminobenzoyl-derivatives deriving from these salts, further the salts of the 0-, mor p-aminobenzyl-pyridine, or of aminophenazonium compounds (safranine). Also diazotizable aminoazo-dyestuffs with a quaternary ammonium group may be considered, such as the salts of the trimethyl (p -aminobenzol azophenyl ammonium or the coupling-products of diazotized aromatic amino-ammonium compounds with mtoluidine, oc-l'lillilhthYlEtl'IllIlQ or with other socalled intermediate components.

The particular technical value of the basic azodyestuffs synthesized according to the above described principles, compared with similar wellknown dyestuffs (of. e. g. Schultz-Julius, Farbstofitabellen 191 i, Nos. 126, 240) is to be seen on the one hand, in the fact that the new products are faster to light, and on the other hand that they are capable of fixing on the cellulose fibre substantive dyestuffs of an acid character so that they are fast to washing. These Washing-fast dyeings can be obtained either by producing first and in the usual -manner a substantive dyeing which is then dyed over, in the same or in a fresh bath, with the basic dyestufi, or in coating first the fibre with the basic dyestuif and in dyeing it subsequently over with the acid dyestuff. This second procedure is applied if the basic dyestufi is likewise substantive such as to adhere evenly upon the cellulose fibre. In both cases one obtains dyeings which are particularly fast to washing, if the basic dyestuff contains no less than-two quaternary ammonium, groups. If one dyes with the basic dyestuff the latter may also serve as a mordant for non-substantive acid dyestuffs, though such dyeings, as we known by experience, are not very fast to washing. In any case there is a possibility of using non-substantive acid dyestuffs for the dyeing of the cellulose fibre.

On the other hand one obtains excellent fastness properties if substantive dyestuffs, produced according to the present invention, are dyed on the cellulose fibre and subsequently treated with tannic materials and particularly with those of the pyrogallolor ellagic acid type, or vice versa if one impregnates the fibre first with the tannic acid solution and treats it subsequently with the dyestuff-solution. A further augmentation of the fastness-propertiesof the thus obtained dyeings, especially of the fastness to light and washing, is obtained by a subsequent treatment of the dyeings with the solutions of salts of lacquer or lakefor ning metals such as aluminium, iron, chromium, nickel, copper and the like.

Of a technical value are also the combinations of the present basic dyestuffs with acid mordant dyestuffs, the value being particularly due to the fact that it is possible to render such combinations most resistant to light and washing by an after-treatment with metal-salts.

It is a remarkable fact that the textiles dyed with the new dyestuffs are of an agreeable smoothness and softness to the touch if they are subsequently treated with solutions of soaps or sap-like strfis such as sulfonated fats and oils, fatty alcohol sulfonates or the like.

Example 1 262 weight parts of bis-(2,3'-hydroxynaphthoyl) benzidine, ea ily obtainable according to the German Patent No. 293,897 from two molecules of 2,3-hydroxynaphthoic acid and one molecule of benzidine in condensing by means of phosphor-trichloride or thionyl-chloride, are dissolved cold in 3000 parts of alcohol with an admixture of 150 parts of potassium hydroxide. To the icecooled alcoholic solution a diazo solution is gradually added, under vigorous stirring, which is made in the usual manner of 262 parts from trimethyl-m-amin.ophenyl ammonium methylsulfate, 2500 parts of water, 216 parts of 38% hydrochloric acid and 69 parts of sodium nitrite. The thus formed disazo dyestufi' results as a darkred sediment. When the coupling is terminated, the sediment is removed by suction or by pressure, then it is dissolved in hot water with the addition of a small amount of mineral acid. Should it be necessary one filters out insoluble matters, then one precipitates the dyestuff solution while hot with salt, whereupon one filters again and dries in vacuo at a slow heat.

The thus obtained dyestuff dyes cotton orange from a saline bath which is neutral or slightly acidified with acetic acid. The dyeing subsequently treated for 20 to 30 minutes in a second bath with a hot aqueous solution of approximately the same amount of Congo red, gives a red which is excellently fast to washing and, peculiarly, a little more bluish than an ordinary Congo dyeing in spite of the orange-ground. Also combined with a great number of other substantive dyestuffs or with tannic acids in a similar manner, the new dyestufi gives dyeings which are particularly fast to washing. In the case of the dyeing over with tannic acids, it is recommended that one proceed to a subsequent treatment of the combined dyeing with alkali metal bichromate and copper sulfate in order to obtain a perfect fastness to washing and light.

If for the present example the diazo component is replaced by other quaternary amino-ammonium salts,e.g.by the trimethyl-(2,4-dimethyl- 5-amino-phenyl-)ammonium-methylsulfate, the trimethyl (3-amino-4-methoxyphenol-)ammonium chloride or by the trimethyl-(S-amino-lnaphthyl-) ammonium chloride, one obtains dyestuffs colouring the cellulose fibre yellowish red to pure red, which possess quite similar properties as hereinbefore described.

Example 2 190 weight parts of bis-acetoacetyl-tolidine obtainable in well known manner by condensing two molecules of aceto acetic ester with one molecule of 3,3'-dimethyl-4,4'-diamino-diphenyl in boiling xylol, are dissolved cold in a solution of 150 parts of potassium hydroxide in 2500 parts of alcohol. Then one acidifies slightly the solution while stirring vigorously by an addition of glacial acetic acid and to the resulting suspension of the freshly precipitated bis-aceto aoetyl-tolidine, one adds 250 parts of crystallized sodium acetate. The mixture is cooled down to about 5 C. and gradually mixed, under a vigorous stirring, with a diazo solution obtainable in wellknown manner from 262 parts by weight of trimethyl-p-aminophenyl ammonium methylsulfate, 2000 parts of water, 274 parts of 30% hydrochloric acid and 69 parts of sodium nitrite. There results a yellow azo dyestuff. To complete the coupling one adds a 20% soda solution in such an amount that the reaction of the mixture is still slightly acid to litmus. The finished dyestuff is filtered and dried. This dyestuii dyes cotton and viscose silk from a saline bath which is neutral or slightly acidified with acetic acid pure yellow and is applicable in an analogous manner tothe dyestuff described in Example 1.

The coupling can also be done in an alkaline medium by omitting the acidifying of the tolidide solution before the diazo solution is poured in. In this case the addition of sodium acetate is likewise omitted. Analogously to Example 1 it is possible also in the present case to shift the tone from yellow to orange and red-orange by choosing diazo-components of a bathochromic effect.

Erample 3 135 weight parts of aceto-acetic ester are heated together with 600 parts of xylol up to boiling in a vessel provided with a stirring means and a column apparatus acting as a reflux cooler. Then a solution of 136 parts of p-amino-dlmethylaniline in 400 parts of xylol is gradually and under continued boiling poured in and the influx regulated so that the developing alcohol escapes regularly at the upper end of the column. The reaction is finished as soon as the development of alcoholic vapors ceases after the completed influx of the amine solution and the continued boiling. A sample of the clear react-ion liquid solidifies while cooling to a paste, which is composed of crystals of p-dimethylamino-aceto-acetic anilide. Now one cools the mass down to 95 C., whereupon the stirring means is set in motion and 150 parts of dimethyl sulfate are gradually poured in at 90 to 100 C. Immediately the separation of the reaction product begins and it is completed by a subsequent stirring for 3 hours at 95 C. Now one adds 1000 parts of Water whereupon the reaction product forms rapidly a solution; one separates the aqueous layer from the xylol layer and neutralizes the former with soda. By evaporating in vacuo one can now obtain the formed trimethyl-p-acetoacetylaminophenyl-ammoniumrnethylsulfate of the formula in the form of a viscous transparent and hygroscopic mass. For the production of azo dyestuffs it is, however, sufficient to determine the proportion of substance capable of coupling contained in the aqueous solution by titration with adjusted p-nitrobenzol-diazonium solution in the usual way.

By coupling 2 molecules of the above described compound with 1 molecule of diazotized benzidine in a soda alkaline solution under the usual conditions, one obtains a dyestuff soluble in water and capable of being separated by salt, which in the form of small yellow flakes.

Example 4 136 parts of m-amino-dimethylaniline are dissolved in 950 parts of pyridine. This solution is cooled down to about 5 C. whereupon a solution of 204 parts of p-nitrobenzoylchloride in 220 parts of acetone are gradually poured in under stirring and cooling; towards the end of the influx the condensation product begins to precipitate itself Now one heats the mass slowly up to 40-45 C., eeps this temperature for a while, then one renders it slightly alkaline with a 20% soda solution, whereupon the whole is kept cold during the night. The

a separated crystals are filtered off, washed out Lin with 95% alcohol and then with water, whereupon they are dried. From the mother-lyes one obtains further quantities of the condensation product by diluting to a high degree with water. The total yield of p-nitrobenzyl-m-amino-dimethyl-aniline amounts to 86-87% oi the theoretical yield. 235 parts of the nitrobenzoyl compound are suspended in 3650 parts of toluoi; the mixture is heated under stirring to 95 C., whereby nearly all is dissolved. Now 150 parts of dimethyl sulfate are poured in slowly at 90-100" C. and under continuous stirring; the stirring is continued at the same temperature until a cooled sample of the reaction mixture ceases to separate ofi" any red sediment of unaltered initial material, which will occur after approximately 3 to 5 hours. Then one cools. the mass down to room temperature. In order to destroy the excess dimethyl sulfate, one adds concentrated ammonia water until the alkaline reaction is permanent, whereupon about 3500 parts of hot water are added. One stirs while warm until all is dissolved, then one separates the aqueous layer from the toluol layer. If necessary one filters the watery layer while hot and the filtrate is then cooled down. During this operation the greater part of the formed trimethyl-(p'-nitrobenzoyl-maminophenyl) ammonium-methyl sulfate of the formula separates in colorless crystals which are covered with a small amount of cold water and then dried. From the mothenuye one can still separate out a small quantity of the compound. by salting out. The total yield is about 85% of the theoretical.

The reduction of the nitro-compound to the corresponding amino-compound is done in known manner by gradually introducing the same into a boiling mixture of water, cast iron chips and a little acetic acid, a quantity of cast iron being employed which is about equal or somewhat larger than the amount of the nitro-compound to be reduced. When the reduction which progrosses smoothly, is terminated, one boils the mass for an additional half an hour, then one renders it slightly alkaline using soda, one filters it from the iron while hot and the filtrate is rendered neutral to litmus. Now, should it be necessary, one evaporates the solution to such a degree that the volume amounts to about '7 litres per kilogram of the applied nitro-compound, then one adds 250 g. of common salt per litre of solution and one cools the mass down intensively, expediently to -5 C. The crystallization being terminated one filters oil the crystals and dries them at about 90 C. The yield of trimethyl- (p-amino'benzoy1-m-aminophenyl ammonium chloride is not far from the theoretical yield.

The diazonium solution made in the usual manner at about C. by means of hydrochloric acid and sodium nitrite couples with the well known coupling components such as phenol, fi-naphthoi, 2,3-hydroxynaphthoic acid anilide, etc. and forms basic azo dyestuffs of tones which diiTer but little from those obtained from diazotized p-nitraniline or its sulfonic acids with the same components, but the new dyestufis distinguish themselves by a better fastness to light and an. increased afinity for the cellulose fibre.

By combining the above diasonium solution with a weak acetic acid or soda alkaline solution of the triinethyl-pacetoacetyl-aminophenyl-ammonium-methylsuliate described. in Example 3, one obtains a yellow substantive dyestuff which possesses the properties of the dyestuffs in Examples l to 3.

By introducing in the present example an intermediate component between the diazoand the coupling components, such as ni-toluidine, a-naphthylamine or the like, one obtains dyestuffs of a still higher afiinity for the cellulose fibre.

For instance the m--toluidine serving as the intermediate component supplies a strongly substantive brownish yellow dyestuff of a good fixing power for acid dyestufis and tannic acids.

Example 5 316 parts of aminobenzyl-methyl-piperidiniummethylsulfate (obtained by the mononitrating of benzylchloride, by the reaction of the obtained mixture of 0- and p-nitrobenzylchloride upon piperidine, by forming the additive compound with dimethylsulfate and by the reductionv of the nitro group), dissolved in 5000 parts of water, are diazotized with 220 parts of fuming hydrochloric acid with 38% H01 and 69 parts of sodium nitrite. The diazo solution is poured under stirring into a solution, cooled down to less than C., of 312 parts of trimethyl-(El-aminonaphthyl-2-) ammonium-methylsulfate (obtained from 8-nitro-2-naphthylamine by an exhaustive methylation with dimethylsulfate and subsequent reduction of the nitro group) in 5000 parts of water. To complete the coupling which occurs smoothly, one adds a soda solution until the Congo acid reaction of the liquid just vanishes. Then one acidifies again with 220 parts of 38% hydrochloric acid, and diazotizos with 69 parts of sodium nitrite, whereby a tone conversion from bluish red to yellow brown will rapidly occur. Then one introduces gradually during stirring the diazo-solution into an ice-cold solution of 268 parts of 2,3-hydroxy-naphthoic acid-anilide and 200 parts of caustic soda in 7000 parts of water, wherein the phenolphthalein-alkaline reaction of the mixture must continue until the end. The coupling being terminated the precipitated dyestuff is filtered off and dissolved in hot water together with an amount of hydrochloric acid, that a sample salted out shows a slight Congo acid reaction; then one filters the solution to separate insoluble matters should it be necessary, and the filtrate is salted out. After cooling the purified dyestuff is filtered oil and dried. It constitutes a dark violet resin brittle when cold, it is highly substantive and dyes the cellulose Lil fibre violet. The dyeings are of a good fastness to washing. Its structural formula corresponding to the method of formation is indicated hereafter, i. e. for the para-derivative:

a diazotized aromatic amine having at least one quaternary ammonium group with a radical of a coupling component comprising an aromatic diaceto acetyl diamine.

3. As new articles of manufacture, the water soluble azo dyestufis containing the radical of a diazotized aromatic amine having at least one quaternary ammonium group with the radical of a coupling component comprising a diaceto acetyl derivative of a diamino diphenyl.

4. The azo dyestuif having the following struc- What I claim is:

1. Method of producing highly basic azo dyestufis with at least one quaternary ammonium groupin the molecule, characterized in the coupling of diazotized quaternary aromatic ammonium compounds with aromatic cli-acetoacetyldiamines.

2. As new articles of manufacture, the Water tuml formula 3 soluble azo dyestuffs containing the radical of CHr-NON=N-CH CH-N=N-NCH: 1 2o CH: ('30 ()0 CH3 CHZO4S CH: CH: 304C113 ERIK SCHIRM. 

